Extension tube for electric vacuum cleaner

ABSTRACT

The purpose of the present invention is to provide an extension tube for electric vacuum cleaner, which has a reduced weight, is easier to grip, and is easier to operate. This extension tube for electric vacuum cleaner comprises a tube body and a conductive unit provided so as to pass through the interior of the tube body. The conductive unit has a conductive cable and a hollow plate which accommodates the conductive cable.

TECHNICAL Field

The present invention relates to an extension tube for an electricvacuum cleaner.

BACKGROUND ART

To take an example of a traditional extension tube for an electricvacuum cleaner, Patent Literature 1 suggests an extension tubecomprising a tube body; a cover attached to an outer surface of the tubebody and extending in a longitudinal direction; an insulating resinplate provided at a space between the tube body and the cover; and leadwires placed on and supported by the insulating resin plate, whereinboth ends of each lead wire are exposed to the outside so as to beelectrically connectable with terminals of a vacuum cleaner body and ofan intake port body.

CITATION LIST Patent Literature [PTL 1] Japanese Unexamined PatentApplication Publication No. 2012-249699 SUMMARY OF INVENTION TechnicalProblem

The extension tube described in Patent Literature 1 becomes thickbecause of comprising the insulating resin plate; the lead wires; andthe cover, each of which being placed on an outer surface of the tubebody and extending along a longitudinal direction, resulting in anincrease in a total weight of the extension tube in addition toimpairing ease of gripping the extension tube; therefore, there arises aproblem that operability of the extension tube decreases at a time whendetermining a direction of the intake port body with use of theextension tube.

In view of such a problem above, the present invention has an object ofproviding an extension tube for an electric vacuum cleaner having areduced weight and being easier to be gripped in addition to beingeasier to be operated.

Solutions to Problem

The present invention provides an extension tube for an electric vacuumcleaner, the extension tube comprising a tube body and a conductive unitprovided so as to be laid in the tube body,

-   -   wherein the conductive unit includes conductive cables and a        hollow plate that contains the conductive cables.

The extension tube according to the present invention is applicable to,for example, an electric vacuum cleaner in which an intake port bodyhaving a motor-driven rotary brush incorporated therein is connected toa vacuum cleaner body and which supplies electric power to the motorfrom the vacuum cleaner body via the extension tube to clean a floorsurface while rotating the rotary brush in the intake port body. Inaddition, in this extension tube, the conductive unit is compactlyprovided inside the tube body, and the tube body is not so thick.Therefore, the extension tube has reduced weight and is easier to begripped, which leads to improved operability when a user changes thedirection of movement of the intake port body via the extension tube.BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 illustrates a left-side view of an electric vacuum cleaner inaccordance with Embodiment 1 of the present invention.

FIG. 2 illustrates a perspective view of the vacuum cleaner body of theelectric vacuum cleaner in accordance with Embodiment 1.

FIG. 3 illustrates a left-side cross-section view of an inner structureof an operating portion in a handle of the vacuum cleaner body of FIG.2.

FIG. 4 illustrates a left-side cross-section view of an inner structureof the vacuum cleaner body of FIG. 2.

FIG. 5 illustrates a perspective view of a disassembled housing of adrive unit of the vacuum cleaner body of FIG. 2.

FIG. 6(A) illustrates the electric vacuum cleaner in accordance withEmbodiment 1 that is placed on a floor; and FIG. 6(B) illustrates theelectric vacuum cleaner in accordance with Embodiment 1 that lies on afloor.

FIG. 7 illustrates an exploded view of the drive unit of the electricvacuum cleaner in accordance with Embodiment 1.

FIG. 8(A) illustrates a left-side view of the drive unit; and FIG. 8(B)illustrates a left-side view of the vacuum cleaner body.

FIG. 9(A) illustrates a cross-section view taken from line I-I of Fig.A(A); and FIG. 9(B) illustrates a cross-section view taken from line I-Iof Fig. A(B).

FIG. 10(A) illustrates a perspective view of a dust cup to be installedin the electric vacuum cleaner in accordance with Embodiment 1; and FIG.10(B) illustrates an exploded view of the dust cup.

FIG. 11(A) illustrates a front view of the dust cup to be installed inthe electric vacuum cleaner in accordance with Embodiment 1; FIG. 11(B)illustrates a cross-section view taken from line I-I of FIG. 11(A); andFIG. 11(C) illustrates a cross-section view taken from line II-II ofFIG. 11(A).

FIG. 12(A) illustrates a plan cross-section view of a lower part of adust cup unit; and FIG. 12(B) illustrates a side cross-section view ofthe dust cup unit.

FIG. 13(A) illustrates a front view of an extension tube of the electricvacuum cleaner in accordance with Embodiment 1; FIG. 13(B) illustrates aside view of the extension tube; and FIG. 13(C) illustrates across-section view taken from line I-I of FIG. 13(A).

FIG. 14 illustrates an exploded view of the extension tube of FIG.13(A).

FIG. 15 illustrates an explanatory view of an inner structure of a firstconnecting pipe unit and a second connecting pipe unit of the extensiontube of FIG. 13(A) which are viewed from the front side.

FIG. 16 illustrates a transverse cross-section view of the tube body ofthe extension tube of FIG. 13(A).

FIG. 17 illustrates an explanatory view of a layered structure of thetube body of the extension tube of FIG. 13(A).

FIG. 18(A) illustrates a front view of a conductive unit in theextension tube of FIG. 13(A); FIG. 18(B) illustrates a side view of theconductive unit; and FIG. 18(C) illustrates a rear view of theconductive unit.

FIG. 19 illustrates an exploded view of the conductive unit of FIG.18(A).

FIG. 20(A) illustrates a cross-section view taken from line I-I of FIG.18(A); FIG. 20(B) illustrates a cross-section view taken from line II-IIof FIG. 18(A); and FIG. 20(C) illustrates a cross-section view takenfrom line III-III of FIG. 18(A).

FIG. 21 illustrates lead wires in a cover plate of the conductive unitof FIG. 18(A).

FIG. 22 illustrates a transverse cross-section view of the firstconnecting pipe unit of the extension tube of FIG. 13(A).

FIG. 23 illustrates a bottom view of an intake port body of the electricvacuum cleaner in accordance with Embodiment 1.

FIG. 24 illustrates a side view of the intake port body illustrated inFIG. 23.

FIG. 25 illustrates a cross-section view of the intake port body takenfrom line I-I of FIG. 23.

FIG. 26 illustrates a cross-section view of the intake port body takenfrom line II-II of FIG. 23.

DESCRIPTION OF EMBODIMENTS Embodiment 1

FIG. 1 illustrates a left-side view of an electric vacuum cleaner inaccordance with Embodiment 1 of the present invention.

An electric vacuum cleaner 1 in accordance with Embodiment 1 comprises avacuum cleaner body 10, an extension tube 20, and an intake port body40. The extension tube may or may not have a structure that can extendthe tube itself. Unlike a handheld vacuum cleaner in which an intakeport body is attached directly to the vacuum cleaner body, the vacuumcleaner of the present invention can be used as a stick vacuum cleanerhaving the extension tube installed between the intake port body and thevacuum cleaner body, and has a long distance from the electric vacuumcleaner body to the intake port body.

Vacuum Cleaner Body

FIG. 2 illustrates a perspective view of the vacuum cleaner body of theelectric vacuum cleaner in accordance with Embodiment 1; and FIG. 3illustrates a left-side cross-section view of an inner structure of anoperating portion in a handle of the vacuum cleaner body of FIG. 2. FIG.4 illustrates a left-side cross-section view of an inner structure ofthe vacuum cleaner body of FIG. 2; and FIG. 5 illustrates a perspectiveview of a disassembled housing of a drive unit of the vacuum cleanerbody of FIG. 2. FIG. 6(A) illustrates the electric vacuum cleaner inaccordance with Embodiment 1 that is placed on a floor; and FIG. 6(B)illustrates the electric vacuum cleaner in accordance with Embodiment 1that lies on a floor.

The vacuum cleaner body 10 comprises a drive unit 11, a dust cup unit 12detachably attached to the drive unit 11, and a battery 13.

Drive Unit

As illustrated in FIG. 2, FIG. 4, and FIG. 5, the drive unit 11 has abody 11 a containing an electric blower 11 am; a battery mounting part11 b communicating with the body 11 a; a handle 11 c having two endsthat communicate with the body 11 a and the battery mounting part 11 b,respectively; and an intake tube 11 d that communicates with a jointpart connecting the body 11 a to the handle 11 c and projects in anopposite direction from the handle 11 c.

The component parts of the drive unit 11 will be described below on thebasis of the following specific directions: The intake tube 11 d side isregarded as the front side; the handle 11 c side is regarded as the rearside; the battery mounting part 11 b side is regarded as the bottomside; the opposite side from the battery mounting part 11 b is regardedas the upper side; the left side in a state where the handle 11 c ispositioned frontward is regarded as a left direction; and the right sidein this state of the handle is regarded as a right direction.

The body 11 a is configured to have a shell which is a cylindricalhousing part having a front opening 11 a ₁, and this front opening 11 a₁ has lattice-shaped ribs.

The body 11 a has a fitting convex portion 11 ax placed on its topsurface, and the fitting convex portion 11 ax has on its top surface anopening that draws lead wires from the body 11 a to the outside.

The body 11 a has an inner flange along a fringe of the front opening 11a ₁, and a lower part of the inner flange is a wide-width inner flangewide portion 11 a ₁₁.

The inner flange wide portion 11 a ₁₁ is provided with the followingcomponent parts: a locking convex portion 11 a ₁₂ and an engagingconcave portion 11 a ₁₃ detachably locking to a locking concave portion12 c ₁₁ and an engaging nail 12 b ₂₃, respectively, of a second lockingmechanical section 12 b ₂, which is provided to the dust cup unit 12(which will be described below). The locking convex portion 11 a ₁₂projects toward the bottom side, and the engaging concave portion 11 a₁₃ opens toward the front side.

The battery mounting part 11 b opens toward the bottom side and the rearside, and has a concave portion having terminals in its back that areelectrically connectable with terminals of the battery 13; and thebattery mounting part is configured to enable the battery 13 to beinserted into its concave portion from its rear side and to be mountedtherein and also is configured to enable the battery 13 to be drawntherefrom toward the rear side and to be removed (or detached) from theconcave portion. The battery mounting part 11 b is configured to haveconcave channels that extend in a front-rear direction and are placed ona right-left inner side surface of the concave portion. The battery 13is configured to have convex portions on its right-left side surface sothat the convex portions on the both sides can respectively slide andfit into the concave channels on the both sides at a time when thebattery 13 is mounted into the battery mounting part 11 b.

The battery mounting part 11 b has an exhaust opening 11 bx on aright-side surface of a housing of the battery mounting part, and theexhaust opening is to exhaust an air current from the electric blower 11am to the outside (see FIG. 4).

The handle 11 c has an upper curved portion 11 c ₁ and a lower curvedportion 11 c ₂, both of which roughly having the shape of the letter“U”; and the upper curved portion 11 c ₁ has an operating portion 11 eon its external side.

As illustrated in FIG. 3 and FIG. 4, the operating portion 11 e has thefollowing component parts: a concave portion 11 e ₁ formed in a plastichousing that constitutes the upper curved portion 11 c ₁ of the handle11 c; a pad 11 e ₂ that is made of an elastic material (rubber,elastomer, etc.) and is mounted on the external side of the concaveportion 11 e ₁; and a switch unit 11 e ₃ provided inside the concaveportion 11 e ₁ (inside the housing).

The operating portion 11 e has a convex rib 11 e ₁₁ in a center of theconcave portion 11 e ₁; and the convex rib 11 e ₁₁ has a pair ofU-shaped slits formed at its front and rear positions; and an inner areaof each U-shaped slit is an elastic and deformable blade spring 11 e ₁₂.Each blade spring 11 e ₁₂ has a convex portion on its lower surface. TheU-shaped slits of the concave portion 11 e ₁ have locking openingsformed in front of and the back of the slits, respectively; and a pairof front and rear inserting locking fragments 11 e ₂₄ of the pad 11 e ₂(which will be described below) are respectively inserted into thelocking openings.

The pad 11 e ₂ has, on its upper surface side, concave portions 11 e ₂₂and 11 e ₂₃ in front of and the back of a center portion 11 e ₂₁,respectively. The pad 11 e ₂ has, on its lower surface side, a convexportion at a corresponding position of the center portion 11 e ₂₁ and ata corresponding position of the pair of concave portions 11 e ₂₂ and 11e ₂₃; and these convex portions have the inserting locking fragments 11e ₂₄ formed at their front and rear positions, respectively. The centerportion 11 e ₂₁ comes in contact with the convex rib 11 e ₁₁; and theconcave portions 11 e ₂₂ and 11 e ₂₃ placed at the front and at the backcome in contact with the blade springs 11 e ₁₂, respectively.

The switch unit 11 e ₃ in the handle 11 c has a circuit board 11 e ₃₁supported and fixed by a rib structure in the upper curved portion 11 c₁ and also has a pair of front switch 11 e ₃₂ and rear switch 11 e ₃₃provided on the circuit board 11 e ₃₁.

In this operating portion 11 e, the circuit board 11 e ₃₁ is configuredto enable the following operations. For example, power is turned on bypushing the front switch 11 e ₃₂ or the rear switch 11 e ₃₃. After that,pushing the front switch 11 e ₃₂ once turns on a high mode; pushing thefront switch twice turns on a standard mode; and pushing the frontswitch three times or more allows these modes to repeat. The power canbe shut down by pushing the rear switch 11 e ₃₃ when the power is on.

When a user operates the operating portion 11 e and pushes the frontconcave portion 11 e ₂₂ or the rear concave portion 11 e ₂₃ of the pad11 e ₂ with his finger, the front switch 11 e ₃₂ or the rear switch 11 e₃₃ is pushed by the blade spring 11 e ₁₂. If the user squeezes tight onthe pad 11 e ₂ during cleaning, the user's palm would not push in thefront concave portion 11 e ₂₂ or the rear concave portion 11 e ₂₃, and amisoperation unintended by the user is prevented, because the centerportion 11 e ₂₁ placed between the front concave portion 11 e ₂₂ and therear concave portion 11 e ₂₃ of the pad 11 e ₂ projects and is supportedby the convex rib 11 e ₁₁.

As illustrated in FIG. 5, the intake tube 11 d and the handle 11 e areassembled (or built) with a first member 11 x, a second member 11 y, anda third member 11 z (which will be described below).

As illustrated in FIG. 4 and FIG. 5, the first member 11 x extends in afront-rear direction and has at its front end a concave portioncontaining a locking member 11 x ₁, a hooking member 11 x ₂, etc.; andthe first member also has at its rear end a fitting opening 11 x ₃ intowhich the fitting convex portion 11 ax of the body 11 a is fitted.

The locking member 11 x ₁ is swingably installed in the first member 11x so as to rotate on a horizontal axis; and in a state where theabove-described component parts are assembled, the front end of thelocking member 11 x functions as a push button that projects downwardfrom an opening formed on the first member 11 x to the outside. A rearend of the locking member 11 x functions as an engaging nail 11 x ₁₁that detachably engages with an engaging concave portion 22 a ₃₁ (seeFIGS. 9(A) to 9(C)) of a first connecting pipe unit 22 (to be describedbelow) of the extension tube 20 at a time when the extension tube 20 isinserted into a front opening 11 d ₁ of the intake tube 11 d. In a statewhere the above-described component parts are assembled, a coil springis placed between the first member 11 x and the second member 11 y, andbiases downward the front end of the locking member 11 x (to theoutside).

The hooking member 11 x ₂ detachably locks into a locking concaveportion 12 a ₂₁ (to be described below) of the dust cup unit 12installed in the vacuum cleaner body 10, and projects downward from theopening formed on the first member 11 x to the outside.

The first member 11 x has, on its left-side surface of its middle partin a front-rear direction, a connection port 11 x ₄ that is connectedwith an outflow port 11 y ₁₁ (to be described below) of the secondmember 11 y; and the first member also has, on its lower surface side ofits rear end, a concave portion, where contains a first lockingmechanical section 12 b ₁, and a concave portion 11 x ₁₂, into which apositioning convex portion 12 c ₂₁ is fitted, (which will be describedbelow) of the dust cup unit 12 installed in the vacuum cleaner body 10.

The second member 11 y has the following component parts: a front tube11 y ₁ communicating the front opening 11 d ₁ with the outflow port 11 y₁₁; an intermediate rib structure portion 11 y ₂ communicating with thefront tube 11 y ₁; and an inner handle structure portion 11 y ₃communicating with the intermediate rib structure portion 11 y ₂ so asto form an inner part of the handle 11 c. The front tube 11 y ₁ has, atits lower surface side-front end, a pair of female terminals 11 y ₁₂electrically connected with the pair of lead wires (not illustrated),respectively, that is drawn from the body 11 a; and the inner handlestructure portion 11 y ₃ contains the switch unit 11 e ₃ of theoperating portion 11 e in its curved intermediate portion.

The third member 11 z is to cover the intermediate rib structure portion11 y ₂ and the inner handle structure portion 11 y ₃, and has the pad 11e ₂ of the operating portion 11 e in its intermediate portion.

The battery mounting part 11 b has at its rear part a junction 11 b ₁joining with a rear end of the second member 11 y and a rear end of thethird member 11 z. This junction 11 b ₁ comprises a fixed projectingportion 11 b ₁₁ and a holding member 11 b ₁₂ provided swingably on thefixed projecting portion 11 b ₁₁. The holding member 11 b ₁₂ is operatedat a time when the battery 13 is removed (or detached).

One example of how the first member 11 x, the second member 11 y, andthe third member 11 z are assembled is that firstly the fitting opening11 x ₃ of the first member 11 x is fitted to the fitting convex portion11 ax of the body 11 a.

Secondly the pair of lead wires (not illustrated) drawn from the body 11a is electrically connected with the pair of female terminals 11 y ₁₂ ofthe second member 11 y, respectively; then the pair of female terminals11 y ₁₂ is attached to a front end of the second member 11 y; and thenthe second member 11 y is placed on the first member 11 x. This enablesthe outflow port 11 y ₁₁ of the second member 11 y to be connected withthe connection port 11 x ₄ of the first member 11 x, and enables therear end of the second member 11 y to come in contact with the fixedprojecting portion 11 b ₁₁ of the junction 11 b ₁.

The two component parts—the second member 11 y on top of the firstmember 11 x—are placed in an ultrasonic welding machine; and left andright edges 11 xe of the front end of the first member 11 x areultrasonic-welded onto left and right edges 11 ye of the front tube 11 y₁ of the second member 11 y, respectively. The reference sign 11 w inFIG. 2 indicates a welding portion. The first member 11 x and the secondmember 11 y that are partially ultrasonic-welded as described aboverender any tapping screws unnecessary for coupling these two componentparts, leading to a reduction in the number of parts and a weightreduction. The first member 11 x and the second member 11 y are made of,for example, an ABS resin.

Lastly the holding member 11 b ₁₂ of the junction 11 b ₁ is swung towardthe second member 11 y side, and then the third member 11 z is placed onthe second member 11 y. This enables the rear end of the third member 11z to hold down the holding member 11 b ₁₂.

The third member 11 z is connected with the second member 11 y with useof a tapping screw N; with the result that the rear end of the secondmember 11 y and the rear end of the third member 11 z join with thejunction 11 b ₁; and the handle 11 c and the intake tube 11 d areformed.

As illustrated in FIG. 6(A), in the vacuum cleaner body 10, a supportmember 11 f for supporting the vacuum cleaner body 10 is provided at afront end of the battery mounting part 11 b so that the electric vacuumcleaner 1 can be placed on a floor surface F at a time when cleaning isdiscontinued. An example of a material of the support member 11 f ishard rubber.

This support member 11 f is formed in a curved shape, in which a lowerend thereof slightly protrudes to the front side, as viewed from theside surface side; and as viewed from the front side, the lower endsurface is formed in an arc shape.

Since a space is provided at a lower part of the extension tube 20 ofthe electric vacuum cleaner 1 in the state of FIG. 6 (A), there is apossibility that the extension tube 20 may be damaged if a force isapplied from directly above. In the present invention, by forming thelower end surface of the support member 11 f in an arc shape, breakageof the extension tube 20 is prevented, because when the force is appliedto the extension tube 20 from directly above, the vacuum cleaner losesits balance and collapses, resulting in a state of lying down asillustrated in FIG. 6(B). When cleaning is discontinued, the supportmember 11 f can be placed so as to be hooked on a top plate of a tableor a backrest of a chair so as to lean the electric vacuum cleaner 1,instead of placing the electric vacuum cleaner 1 on the floor surface F.

FIG. 7 illustrates an exploded view of the drive unit of the electricvacuum cleaner in accordance with Embodiment 1; and FIG. 8(A)illustrates a left-side view of the drive unit, and FIG. 8(B)illustrates a left-side view of the vacuum cleaner body. FIG. 9(A)illustrates a cross-section view taken from line I-I of Fig. A(A), andFIG. 9(B) illustrates a cross-section view taken from line I-I of Fig.A(B).

In the following, the component parts of the drive unit 11 will befurther described through the use of FIG. 2 to FIG. 9.

The body 11 a of the drive unit 11 includes a pair of left electricblower cover 11 ac ₁ and right electric blower cover 11 ac ₂ for housingthe electric blower 11 am.

The front opening 11 a ₁ of the body 11 a is integrally formed at afront end of the left electric blower cover 11 ac ₁; and a half portion11 ax ₁ of the fitting convex portion 11 ax is integrally formed on eachof the left electric blower cover 11 ac ₁ and the right electric blowercover 11 ac ₂. The locking convex portion 11 a ₁₂ is installed in thefront opening 11 a ₁.

The body 11 a has in its inside a pair of vibration-preventing rubberparts 11 ac ₃ that secures a rear end of the electric blower 11 am tothe pair of left electric blower cover 11 ac ₁ and right electric blowercover 11 ac ₂ and also has a packing 11 ac ₄ placed between a front endof the electric blower 11 am and an inner surface of a periphery of thefront opening 11 a ₁.

The battery mounting part 11 b of the drive unit 11 includes a pair ofleft battery mounting part housing 11 bc ₁ and right battery mountingpart housing 11 bc ₂ connected by screws (not illustrated) with a lowerpart of the body 11 a.

The right battery mounting part housing 11 bc ₂ has the exhaust opening11 bx formed on its side surface; and at a front end and a rear end ofthe left battery mounting part housing 11 bc ₁ and the right batterymounting part housing 11 bc ₂ each, a pair of half portions 11 bc ₃,which becomes a core of the support member 11 f, and a pair of halfportions 11 bc ₄ of the fixed projecting portion 11 b ₁₁ are integrallyformed. When assembling the pair of left battery mounting part housing11 bc ₁ and right battery mounting part housing 11 bc ₂, the holdingmember 11 b ₁₂ is swingably attached to the pair of half portions 11 bc₄; and the support member 11 f is attached so as to cover the pair ofhalf portions 11 bc ₃ after assembly. In this case, the support member11 f may be made of rubber to cover these half portions. Also, thesehalf portions may be pasted with an adhesive.

A partition plate 11 bc ₅ is continuously connected from the front endto the rear end of each of the battery mounting part housings 11 bc ₁and 11 bc ₂; and at a lower end of a side wall of the battery mountingpart housings, a lower end side wall portion 11 bc ₆ forming a concavechannel for supporting a convex portion 13 b on the left and right sidesurfaces of the battery 13 is continuously provided so as to be slidablein the front-rear direction.

In the battery mounting part 11 b, there is a circuit board 11 bc ₇having a terminal part 11 bc ₈ that is electrically connectable with aterminal part 13 a of the battery 13.

The handle 11 c and the intake tube 11 d of the drive unit 11 includethe first member 11 x, the second member 11 y, and the third member 11z.

In the first member 11 x, there is provided an LED board 11 xs having aplurality of LED lights which are turned on when the electric vacuumcleaner 1 is operating and when suction power is strong.

In the first member 11 x, a packing 11 xp is attached to an outflow port(not illustrated) joining with the outflow port 11 y ₁₁ of the secondmember 11 y; and the locking member 11 x ₁ and the hooking member 11 x ₂are attached to the front end side of the first member.

In the concave portion 11 x ₁₂ provided at a rear part of the outflowport of the intake tube 11 d, a filter attachment forgetting preventionmember 11 x ₅ is attached so as to be rotatable around a shaft Qextending in the front-rear direction (see FIG. 4 and FIG. 9(A)). Thisfilter attachment forgetting prevention member 11 x ₅ (which may behereinafter referred to as “attachment forgetting prevention member 11 x₅”) has a function of preventing the dust cup unit 12 with no filterportion 12 c from being mounted even if the dust cup unit is about to beattached to the body 11 a of the drive unit 11. This will be describedin detail below.

Dust Cup Unit

FIG. 10(A) illustrates a perspective view of a dust cup to be installedin the electric vacuum cleaner in accordance with Embodiment 1, and FIG.10(B) illustrates an exploded view of the dust cup. FIG. 11(A)illustrates a front view of the dust cup to be installed in the electricvacuum cleaner in accordance with Embodiment 1; FIG. 11(B) illustrates across-section view taken from line I-I of FIG. 11(A); and FIG. 11(C)illustrates a cross-section view taken from line II-II of FIG. 11(A).FIG. 12(A) illustrates a plan cross-section view of a lower part of adust cup unit, and FIG. 12(B) illustrates a side cross-section view ofthe dust cup unit.

The dust cup unit 12 includes the following component parts: acylindrical dust collecting container 12 a having a bottom portion 12 a₁, an outer peripheral portion 12 a ₂, and an opening 12 a ₃; a cupportion 12 b fitted in the opening 12 a ₃ of the dust collectingcontainer 12 a; a filter portion 12 c detachably housed in the cupportion 12 b; and an inner tube 12 d detachably attached to the cupportion 12 b so as to be housed in the dust collecting container 12 a.

Dust Collecting Container

The dust collecting container 12 a is provided with the locking concaveportion 12 a ₂₁ on the bottom portion 12 a ₁ side of the outerperipheral portion 12 a ₂, the locking concave portion lying on a centerline P as viewed from the front; and a locking convex portion 12 a ₂₂ isprovided on the opening 12 a ₃ side on the center line P in the outerperipheral portion 12 a ₂. The dust collecting container 12 a isprovided with an inlet 12 a ₂₃ for taking in dust-containing air at aposition deviated from the center line P in the outer peripheral portion12 a ₂ as viewed from the front.

As illustrated in FIGS. 12(A) and 12(B), the dust collecting container12 a is provided with a quadrangular pyramidal projection 12 a ₄ at aposition deviated from a center position of the bottom portion 12 a ₁towards the external side. This projection 12 a ₄ has a function ofpreventing dust accumulated in a lower space (a space between the dustcollecting container 12 a and a small diameter tube 12 d ₂₁ (to bedescribed below) of the inner tube 12 d) of the dust collectingcontainer 12 a from being swirled by a whirling air current.

Cup Portion

The cup portion 12 b has the following component parts: a bottom portionhaving a center hole and a reverse tapered surface around the centerhole; a cylindrical outer peripheral portion communicating with thebottom portion; the first locking mechanical section 12 b ₁ and thesecond locking mechanical section 12 b ₂ provided on the outerperipheral portion; a pair of arcuate grooves 12 b ₃ provided around thecenter hole on a lower surface of the bottom portion; a packing 12 b ₄provided near the bottom of the outer peripheral portion; and a notchportion 12 b ₅ provided at an opening end on the opposite side to thebottom portion of the outer peripheral portion.

The cup portion 12 b has a detection convex portion 12 b ₆ provided at alateral position of the notch portion 12 b ₅ on its outer peripheralsurface. Functions of this detection convex portion 12 b ₆ will bedescribed in detail below.

The first locking mechanical section 12 b ₁ includes the followingcomponent parts: an inverted U-shaped rib provided on the outerperipheral surface of the cup portion 12 b; a pivoting piece 12 b ₁₁attached to the rib so as to swingably pivot about a horizontal axis; alocking nail 12 b ₁₂ provided at the lower end of the pivoting piece 12b ₁₁ and detachably locking to the locking convex portion 12 a ₂₂ of thedust collecting container 12 a; and a coil spring 12 b ₁₃ that biases ina direction in which the locking nail 12 b ₁₂ locks to the lockingconvex portion 12 a ₂₂.

The second locking mechanical section 12 b ₂ includes the followingcomponent parts: a convex rib provided on the outer peripheral surfaceof the cup portion 12 b; a slide member 12 b ₂₁ attached to this rib ina vertically slidable manner; the engaging nail 12 b ₂₂ provided at anupper end of the slide member 12 b ₂₁ and detachably engaging with theengaging concave portion 11 a ₁₃ of the vacuum cleaner body 10; and acoil spring 12 b ₂₃ that biases in a direction in which the engagingnail 12 b ₂₂ engages with the engaging concave portion 11 a ₁₃.

The second locking mechanical section 12 b ₂ includes the lockingconcave portion 12 c ₁₁ provided in the filter portion 12 c (to bedescribed below) as a component part.

Filter Portion

The filter portion 12 c includes a pleated filter body 12 c ₁ having anannular outer peripheral frame portion and also includes a packingportion 12 c ₂ covering an outer peripheral portion of the outerperipheral frame portion of the filter body 12 c ₁. The locking concaveportion 12 c ₁₁ that opens inward in a radial direction is provided onan inner peripheral surface of the outer peripheral frame portion of thefilter body 12 c ₁; and the positioning convex portion 12 c ₂₁ isprovided on the outer peripheral surface of the packing portion 12 c ₂.

The locking concave portion 12 c ₁₁ and the positioning convex portion12 c ₂₁ are disposed substantially opposite to each other.

When the filter portion 12 c is fitted into an opening of the cupportion 12 b, the positioning convex portion 12 c ₂₁ of the filterportion 12 c is dropped into the notch portion 12 b ₅ of the cup portion12 b and is positioned. Then, the locking concave portion 12 c ₁₁ of thefilter portion 12 c is disposed at a position of the second lockingmechanical section 12 b ₂ of the cup portion 12 b. The packing portion12 c ₂ is supported in close contact with a step portion provided on theinner peripheral surface of the opening of the cup portion 12 b.

Inner Tube

The inner tube 12 d has a tubular filter portion 12 d ₁ detachablyattached to the cup portion 12 b and also has a tubular partition member12 d ₂ detachably attached to the tubular filter portion 12 d ₁.

The tubular filter portion 12 d ₁ has a tubular frame 12 d ₁₁ having aplurality of slits extending in an axial direction and also has a meshmember 12 d ₁₂ provided on an outer peripheral portion of the tubularframe 12 d ₁₁.

The tubular frame 12 d ₁₁ has a pair of locking pieces 12 d ₁₁₁, whichare provided at an upper end of the outer peripheral portion of thetubular frame and detachably lock into a pair of arcuate grooves 12 b ₃of the cup portion 12 b, respectively, and also has a pair of lockingpieces 12 d ₁₁₂, which are provided at a lower end of the outerperipheral portion of the tubular frame and detachably lock into a pairof arcuate grooves 12 d ₂₃₁ (to be described below), respectively, ofthe partition member 12 d ₂.

The partition member 12 d ₂ has the following component parts: the smalldiameter tube 12 d ₂₁; a large diameter tube 12 d ₂₂; and a flangeportion 12 d ₂₃ for connecting an upper end of the small diameter tube12 d ₂₁ with an inner circumferential surface of the large diameter tube12 d ₂₂.

The flange portion 12 d ₂₃ has the pair of arcuate grooves 12 d ₂₃₁provided on an upper surface of the flange portion and detachablylocking to the pair of locking pieces 12 d ₁₁₂, respectively, at a lowerend of the tubular filter portion 12 d ₁.

As illustrated in FIGS. 12(A) and 12(B), the large diameter tube 12 d ₂₂has an outer flange 12 d ₂₂₁ at its lower end. This outer flange 12 d₂₂₁ has an elliptical shape in a plan view so that a gap between theouter flange 12 d ₂₂₁ and the dust collecting container 12 a does notbecome even because of being elliptical; and narrow gaps S₁ and widegaps S₂ are formed. This can prevent the dust having been accumulated ina lower part of the dust collecting container 12 a from being blown upby whirling airflow G and also can prevent a decrease in suction powercaused by the dust that attaches to the tubular filter portion 12 d ₁ ofthe inner tube 12 d.

More specifically, the bottom portion 12 a ₁ of the dust collectingcontainer 12 a has the projection 12 a ₄ for preventing the dust fromswirling; however, there is a possibility that the suction power maydecrease, because a distance from the flange portion 12 d ₂₃ of thepartition member 12 d ₂ to the bottom portion 12 a ₁ of the dustcollecting container 12 a is short; and in the absence of the outerflange 12 d ₂₂₁, the dust hitting the projection 12 a ₄ rises up (or isblown up) to the tubular filter portion 12 d ₁ above the partitionmember 12 d ₂ and attaches to the tubular filter portion.

In order to solve this problem, the outer flange 12 d ₂₂₁ is provided ata lower end of the partition member 12 d ₂ so that the dust is notlikely to fly up to the upper side.

If the gap between an outer peripheral surface of the outer flange 12 d₂₂₁ and an inner peripheral surface of the dust collecting container 12a is too narrow, the sucked large dust will not go below the outerflange 12 d ₂₂₁. In the present invention, the gaps are not even—thatis, the narrow gaps S₁ are formed in places where the dust hits theprojection 12 a ₄ and is likely to swirl up, and the wide gaps S₂ areformed in places where the dust is not likely to swirl up—and the outerflange 12 d ₂₂₁ is configured to be oval, allowing the large dust tofall. In the Embodiments of the present invention, the outer flange 12 d₂₂₁ is set to be 61 mm in major diameter D₁, 57 mm in minor diameter D₂,6 mm in narrow gap S₁, and 8 mm in wide gap S₂; however, lengths are notlimited to the above-mentioned lengths.

Since the projection 12 a ₄ is provided at only one place, normally onenarrow gap S₁ should be enough to be placed as well. In the Embodimentsof the present invention, the partition member 12 d ₂ and the tubularfilter portion 12 d ₁ are configured to be detachable and to lock intoarcuate grooves with use of the locking pieces; and since this lockingstructure has a locking mechanism which can lock even if the structureis rotated 180 degrees to the opposite side; and depending on a lockingposition of the partition member 12 d ₂ with respect to the tubularfilter portion 12 d ₁, one narrow gap S₁ may not be enough to be placedat the position where the dust is likely to swirl up; thus the onenarrow gap S₁ is placed to be 180 degrees opposite to the other narrowgap (or is placed at a diametrically opposed location to the othernarrow gap). In other words, even if the partition member 12 d ₂ lockson either side of 180 degrees with respect to the tubular filter portion12 d ₁, the positions of the narrow gaps S₁ with respect to theprojection 12 a ₄ are the same; that is, the outer flange 12 d ₂₂₁ isformed in an elliptical shape so that either one of the narrow gaps S1is always at the position where the dust is likely to swirl up.

In the assembled state of the dust cup unit 12, the small diameter tube12 d ₂₁ of the partition member 12 d ₂ fits to a positioning tube 12 a₂₄ provided on the inner bottom surface of the dust collecting container12 a; and the small diameter tube comes in contact with a packing 12 a₂₅ provided around the positioning tube 12 a ₂₄. In this state, a spaceis formed in the dust collecting container 12 a to accumulate the dustmass in the bottom side of the large diameter tube 12 d ₂₂ of thepartition member 12 d ₂.

Detachability of Dust Cup Unit from Drive Unit

As illustrated in FIGS. 9(A) and 9(B), the attachment forgettingprevention member 11 x ₅ of the drive unit 11 is provided in the intaketube 11 d so as to be rotatable about the shaft Q in a front-reardirection. In a state (illustrated in FIG. 9(A)) in which the dust cupunit 12 is not attached to the drive unit 11, this attachment forgettingprevention member 11 x ₅ has a first contacting portion 11 x ₅₁projecting downward toward the outside from the intake tube 11 d andalso has a second contacting portion 11 x ₅₂ contained in the intaketube 11 d.

When attaching the dust cup unit 12 (with the filter portion 12 c) tothe vacuum cleaner body 10, the locking concave portion 12 a ₂₁ of thedust cup unit 12 is hooked over the hooking member 11 x ₂ of the vacuumcleaner body 10 in a state where the dust cup unit 12 tilts to theintake tube 11 d. Then, by making the dust cup unit 12 be parallel tothe intake tube 11 d with the hooking member 11 x ₂ as a fulcrum, thelocking convex portion 11 a ₁₂ of the vacuum cleaner body 10 locks intothe locking concave portion 12 c ₁₁ of the dust cup unit 12; and theengaging nail 12 b ₂₂ of the second locking mechanical section 12 b ₂ ofthe dust cup unit 12 engages with the engaging concave portion 11 a ₁₃of the drive unit 11, and the installation is completed.

At this time, as illustrated in FIGS. 9(A) and 9(B), the positioningconvex portion 12 c ₂₁ of the filter portion 12 c comes in contact withthe first contacting portion 11 x ₅₁ of the attachment forgettingprevention member 11 x ₅ and pushes the first contacting portion 11 x ₅₁into the concave portion 11 x ₁₂, with the result that the attachmentforgetting prevention member 11 x ₅ rotates; and the second contactingportion 11 x ₅₂ also rotates and protrudes downward toward the outside.However, as the first contacting portion 11 x ₅₁ is pushed deep into theconcave portion 11 x ₁₂, the second contacting portion 11 x ₅₂ is housedin the concave portion 11 x ₁₂ again while approaching (or getting closeto) the attachment forgetting prevention member 11 x ₅. Meanwhile, thedetection convex portion 12 b ₆ of the dust cup unit 12 also movestoward the concave portion 11 x ₁₂; and the detection convex portion 12b ₆ is housed in the concave portion 11 x ₁₂ while avoiding the secondcontacting portion 11 x ₅₂.

When detaching (or removing) the dust cup unit 12 from the vacuumcleaner body 10, it makes it easy to detach (or remove) the dust cupunit by slanting the dust cup unit 12 against the intake tube 11 d withuse of the hooking member 11 x ₂ as a fulcrum while pressing the slidemember 12 b ₂₁ of the second locking mechanical section 12 b ₂ downward.

In the following, through the use of FIGS. 9(A) and 9(B), an examplecase will be given where the dust cup unit without the filter portion 12c in the cup portion 12 b is installed in the drive unit 11.

For example, if a user forgets to install the filter portion 12 c in thecup portion 12 b and attempts to attach the dust cup unit to the driveunit 11, the positioning convex portion 12 c ₂₁ of the filter portion 12c comes in contact with the first contacting portion 11 x ₅₁ of theattachment forgetting prevention member 11 x ₅ so that the firstcontacting portion 11 x ₅₁ cannot be pushed into the concave portion 11x ₁₂, as described above; and the notch portion 12 b ₅ (see FIG. 10(B))of the cup portion 12 b approaches (or moves closer to) the firstcontacting portion 11 x ₅₁. Then, the detection convex portion 12 b ₆ ofthe cup portion 12 b comes in contact with the second contacting portion11 x ₅₂ of the attachment forgetting prevention member 11 x ₅ andattempts to push the second contacting portion 11 x ₅₂ into the concaveportion 11 x ₁₂.

At this time, the detection convex portion 12 b ₆ tries to rotate thesecond contacting portion 11 x ₅₂ toward the opposite side of the firstcontacting portion 11 x ₅₁ side; however, the second contacting portion11 x ₅₂ hits a side wall constituting the concave portion 11 x ₁₂ and isprevented from turning. As a result, since the cup portion 12 b cannotapproach (or cannot come close to) the intake tube 11 d any further, theengaging nail 12 b ₂₂ of the second locking mechanical section 12 b ₂ ofthe dust cup unit cannot engage with the engagement concave portion 11 a₁₃ of the drive unit 11 and cannot lock into the engagement concaveportion; and the dust cup unit (without having the filter portion 12 c)cannot be attached to the drive unit 11.

This enables the user to notice that the filter portion is not installedin the dust cup unit. Namely, the electric vacuum cleaner of the presentinvention can notify the user of forgetting the installation of thefilter portion and of urging the user to properly use the electricvacuum cleaner; and this can prevent problems such that the electricvacuum cleaner is operated without the filter portion, and the driveunit having sucked in the dust breaks down (or get broken).

Structure of Extension Tube

FIG. 13(A) illustrates a front view of an extension tube of the electricvacuum cleaner in accordance with Embodiment 1; FIG. 13(B) illustrates aside view of the extension tube; and FIG. 13(C) illustrates across-section view taken from line I-I of FIG. 13(A). FIG. 14illustrates an exploded view of the extension tube of FIG. 13(A); FIG.15 illustrates an explanatory view of an inner structure of a firstconnecting pipe unit and a second connecting pipe unit of the extensiontube of FIG. 13(A) which are viewed from the front side; FIG. 16illustrates a transverse cross-section view of the tube body of theextension tube of FIG. 13(A); and FIG. 17 illustrates an explanatoryview of a layered structure of the tube body of the extension tube ofFIG. 13(A).

The extension tube 20 includes the following component parts: a circulartube body 21; a tubular first connecting pipe unit 22 disposed at oneend of the tube body 21 and detachably connected with the vacuum cleanerbody; a tubular second connecting pipe unit 23 disposed at the other endof the tube body 21 and detachably connected with a suction port body;and a conductive unit 24 laid in the first connecting pipe unit 22, thetube body 21, and the second connecting pipe unit 23 therethrough.

Tube Body

The tube body 21 is formed by laminating a plurality of tubular carbonfiber layers 21 a and has a pipe shape (body pipe 21). In accordancewith Embodiment 1, the laminated tubular carbon fiber layers 21 a areformed by layering a first tubular carbon fiber layer 21 a ₁, a secondtubular carbon fiber layer 21 a ₂, and a third tubular carbon fiberlayer 21 a ₃ in this order from the inside. The third tubular carbonfiber layer 21 a ₃ has a resin coating layer 21 b as an outermost layerlaminated on its outer peripheral surface. The tube body is processed asdry carbon. The dry carbon is to be molded in a pressurizable kiln usinga pressure-resistant device capable of setting an inside pressure to behigh.

The first tubular carbon fiber layer 21 a ₁ is made of a unidirectionalcarbon fiber sheet having a plurality of carbon fibers extendingparallel to a pipe longitudinal direction.

The second tubular carbon fiber layer 21 a ₂ and the third tubularcarbon fiber layer 21 a ₃ each are made of a bidirectional carbon fibersheet having a plurality of warps and a plurality of wefts of carbonfibers.

Used as the unidirectional carbon fiber sheet and the bidirectionalcarbon fiber sheet may be commercially-available prepreg sheets in whichthe carbon fibers are impregnated with a resin in advance. Besides thewarps and the wefts, the carbon fibers can be made of diagonally crossedthreads. Combinations of the crossed threads with the warps and thewefts, etc. may be freely arranged.

Using the commercially-available prepreg sheets, the tube body 21 can beprepared by molding and laminating the first tubular carbon fiber layer21 a ₁, the second tubular carbon fiber layer 21 a ₂, and the thirdtubular carbon fiber layer 21 a ₃ one by one using a mold by a knownmethod. For example, a method for wrapping layers around a shaft rod,such as a metal rod, may be used.

In accordance with Embodiment 1, small notches 21 n for positioningconnection positions of the first connecting pipe unit 22 and the secondconnecting pipe unit 23 are formed by notching the already-formed tubebody 21 at opposed positions of its both ends.

In the tube body 21, a thickness T₁ of the first tubular carbon fiberlayer 21 a ₁ is about 0.1 mm; a thickness T₂ of the second tubularcarbon fiber layer and a thickness T₃ of the first tubular carbon fiberlayer 21 a ₁ each is about 0.3 mm; a thickness T₄ of the resin coatinglayer 21 b is about 0.1 mm; and an overall thickness T₅ is about 0.8 mm.The thickness of the first to third tubular carbon fiber layers 21 a ₁to 21 a ₃ is based on a thickness of the unidirectional carbon fibersheet and a thickness of the bidirectional carbon fiber sheet used forforming the layers.

Each tubular carbon fiber layer 21 a has both ends extending in thelongitudinal direction of the tube; and end surfaces of these both endshave end surface contacting portions 21 ax coming in contact with eachother. The end surface contacting portions 21 ax are formed byfusion-bonding the end surfaces of the both ends of the unidirectionalcarbon fiber sheet and of the bidirectional carbon fiber sheet used forforming each tubular carbon fiber layer 21 a.

In the tube body 21, one of the end surface contacting portions 21 ax ofthe tubular carbon fiber layers 21 a is configured not to overlap withthe end surface contacting portion 21 ax of the adjacent tubular carbonfiber layer 21 a. In accordance with Embodiment 1, each end surfacecontacting portion 21 ax is disposed at a position shifted from a centerangle by 120°. In this way, the positions of the end surface contactingportions 21 ax can be shifted uniformly in the circumferentialdirection; and thus the tube body does not have any strong or weakparts, enabling the tube body to be uniformized (or making the tube bodyuniform).

Since each tubular carbon fiber layer 21 a has the end surfacecontacting portion 21 ax, each tubular carbon fiber layer 21 a is formedhaving a uniform thickness without any bumps (or bulges). That is, in acase of simply wrapping one carbon fiber sheet threefold around a metalrod at the time of preparing the tube body, bumps are formed between anend of the first (or undermost) wrapping and a beginning of the second(or middle) wrapping and between an end of the second (or middle)wrapping and a beginning of the third (or outermost) wrapping; however,such bumps are not formed in the tube body 21 of Embodiment 1 becausethe first to third tubular carbon fiber layers 21 a ₁ to 21 a ₃ areindependent from each other. This enables the overall tube body 21 tohave the uniform thickness and to be evenly rigid.

First Connecting Pipe Unit

The first connecting pipe unit 22 is to be connected with the vacuumcleaner body 10 and has a connecting pipe body 22 a, a fragment 22 b,and a (first) cover 22 c.

The connecting pipe body 22 a has the following component parts: a(first) fixed portion 22 a ₁ inserted into one end of the tube body 21and fixed thereto with an adhesive; a (first) terminal holder 22 a ₂communicating with the fixed portion 22 a ₁ and holding a pair of maleterminals 24 a ₂ (to be described below) of the conductive unit 24; andan inserting portion 22 a ₃ communicating with the terminal holder 22 a₂ and inserted into the front opening 11 d ₁ of the vacuum cleaner body10.

The fixed portion 22 a ₁ has at its inner peripheral surface a pair ofreceiving pieces 22 a ₁₁ for receiving one end of a support plate 24 b(to be described below) of the conductive unit 24; and the fixed portionhas a positioning convex portion 22 a ₁₂ engaging with one of thenotches 21 n of the tube body 21 at a boundary portion between the fixedportion and the terminal holder 22 a ₂ on its outer peripheral surface.

The terminal holder 22 a ₂ has a concave portion on the positioningconvex portion 22 a ₁₂ side on its outer circumferential surface; and inthis concave portion, a (first) drawing port 22 a ₂₁ is formed fordrawing the pair of male terminals 24 a ₂ and lead wires 24 a ₁ of theconductive unit 24 from the inside to the outside.

The concave portion of the terminal holder 22 a ₂ is provided with a ribstructure 22 a ₂₂ for holding the pair of male terminals 24 a ₂ parallelto each other at predetermined intervals and also with a boss part 22 a₂₃ into which a tapping screw 22 d for attaching the cover 22 c isscrewed.

The inserting portion 22 a ₃ has, on the positioning convex portion 22 a₁₂ side on an outer peripheral surface of the inserting portion, theengaging concave portion 22 a ₃₁ detachably engaging with the engagingnail 11 x ₁₁ of the locking member 11 x ₁ of the vacuum cleaner body 10.

The fragment 22 b is to cover the drawing port 22 a ₂₁ of the connectingpipe body 22 a through which the pair of lead wires 24 a ₁ is laid; andwhen using the electric vacuum cleaner 1, the fragment functions toprevent dust in the air passing through the extension tube 20 fromflowing from the drawing port 22 a ₂ 1 to the male terminal 24 a ₂ side,and protects the male terminals 24 a ₂.

The cover 22 c covers the concave portion of the terminal holder 22 a ₂of the connecting pipe body 22 a by screwing the tapping screw 22 d intothe boss part 22 a ₂₃; and the cover presses the fragment 22 b againstthe connecting pipe body 22 a and fixes the fragment to the connectingpipe body.

Second Connecting Pipe Unit

The second connecting pipe unit 23 is connected with the intake portbody 40, and has the following component parts: a connecting pipe body23 a, a fragment 23 b, a locking member 23 c, a coil spring 23 d, and a(second) cover 23 e.

The connecting pipe body 23 a has a (second) fixed portion 23 a ₁inserted into the other end of the tube body 21 and fixed thereto withan adhesive, and also has a (second) terminal holder 23 a ₂communicating with the fixed portion 23 a ₁ and holding a pair of femaleterminals 24 a ₃ (which will be described below) of the conductive unit24.

The fixed portion 23 a ₁ has on its inner peripheral surface a pair ofreceiving pieces (not illustrated) for receiving the other end of thesupport plate 24 b of the conductive unit 24; and the fixed portion hasa positioning convex portion 23 a ₁₂ engaging with the other one of thenotches 21 n of the tube body 21 at a boundary portion between the fixedportion and the terminal holder 23 a ₂ on its outer peripheral surface.

The terminal holder 23 a ₂ has a concave portion on the positioningconvex portion 23 a ₁₂ side on its outer peripheral surface; and in thisconcave portion, a (second) drawing port 23 a ₂₁ is formed for drawingthe pair of female terminals 24 a ₃ and the lead wires 24 a ₁ of theconductive unit 24 from the inside to the outside. The concave portionof the terminal holder 23 a ₂ is provided with a rib structure 23 a ₂₂for holding the pair of female terminals 24 a ₃ parallel to each otherat predetermined intervals and also with a boss part 23 a ₂₃ into whicha tapping screw 22 f for attaching the cover 23 e is screwed.

The locking member 23 c has a shaft 23 c ₁ and also has a button 23 c ₂and a locking nail 23 c ₃ communicating with each other so as tosandwich the shaft 23 c ₁ therebetween; and the locking member ismounted in the concave portion of the terminal holder 23 a ₂. The shaft23 c ₁ is rotatably attached to the rib structure 23 a ₂₂. The lockingnail 23 c ₃ is configured to protrude into the connecting pipe body 23 afrom an opening formed on a recess bottom surface of the connecting pipebody 23 a.

The coil spring 23 d is provided in the recess of the connecting pipebody 23 a so as to bias the button 23 c ₂ of the locking member 23 coutwardly.

The fragment 23 b is to cover the drawing port 23 a ₂₁ of the connectingpipe body 23 a through which the pair of lead wires 24 a ₁ is laid; andwhen using the electric vacuum cleaner 1, the fragment functions toprevent dust in the air passing through the extension tube 20 fromflowing from the drawing port 23 a ₂₁ to the female terminal 24 a ₃side, and protects the female terminals 24 a ₃.

The cover 23 e has an opening 23 e ₁ that exposes the button 23 c ₂ ofthe locking member 23 c to the outside. This cover 23 e covers theconcave portion of the terminal holder 23 a ₂ of the connecting pipebody 23 a by screwing the tapping screw 22 f into the boss part 23 a ₂₃,and presses the fragment 23 b against the connecting pipe body 23 a andfixes the fragment to the connecting pipe body so as to prevent thelocking member 23 c from falling off.

Conductive Unit

FIG. 18(A) illustrates a front view of a conductive unit in theextension tube of FIG. 13(A); FIG. 18(B) illustrates a side view of theconductive unit; and FIG. 18(C) illustrates a rear view of theconductive unit. FIG. 19 illustrates an exploded view of the conductiveunit of FIG. 18(A). FIG. 20(A) illustrates a cross-section view takenfrom line I-I of FIG. 18(A); FIG. 20(B) illustrates a cross-section viewtaken from line II-II of FIG. 18(A); and FIG. 20(C) illustrates across-section view taken from line III-III of FIG. 18(A). FIG. 21illustrates lead wires in a cover plate of the conductive unit of FIG.18(A); and FIG. 22 illustrates a transverse cross-section view of thefirst connecting pipe unit of the extension tube of FIG. 13(A). FIGS.20(A) and 20(B) illustrate the cross-section views of projecting pieces24 c ₂, respectively, which will be described below.

The conductive unit 24 includes a pair of conductive cables 24 a and anelongated hollow plate 24 x for housing the pair of conductive cables 24a.

The hollow plate 24 x has the support plate 24 b and a cover plate 24 cthat are configured to contain and sandwich the pair of conductivecables 24 a therebetween; and these component parts are integrated byultrasonic welding at a time of assembling the conductive unit 24. Thesecomponent parts may be integrated by an adhesive.

The pair of conductive cables 24 a and the support plate 24 b are longerin length than the tube body 21; the pair of conductive cables 24 a arelonger in length than the support plate 24 b; and the support plate 24 bis longer in length than the cover plate 24 c.

Each conductive cable 24 a has the lead wires 24 a ₁ covered with aninsulating tube, and also has the pin-shaped male terminals 24 a ₂ andthe clip-shaped female terminals 24 a ₃, both of the terminals beingelectrically connected with both ends of the lead wires 24 a ₁.

In a case where the extension tube 20 is connected with the vacuumcleaner body 10 and the intake port body 40, the male terminals 24 a ₂of the extension tube 20 are plugged into and electrically connectedwith the female terminals 11 y ₁₂, respectively, of the vacuum cleanerbody 10; and the male terminals 42 a (to be described below) of theintake port body 40 are plugged into and electrically connected with thefemale terminals 24 a ₃, respectively, of the extension tube 20 (seeFIG. 23).

The support plate 24 b has a base portion 24 b ₁ having a concavetransverse plane and also has a pair of hooking pieces 24 b ₂ providedalong upper end portions of both side surfaces of the base portion 24 b₁; and the support plate is made of an insulating resin (such as an ABSresin).

A bottom of the base portion 24 b ₁ of the support plate 24 b forreceiving the cover plate 24 c is flat.

The cover plate 24 c has a base portion 24 c ₁ whose transverse plane isnearly m-shaped, and also has the projecting pieces 24 c ₂ provided onthe outer surface of both end portions of the base portion 24 c ₁; andthe cover plate is made of an insulating resin (such as an ABS resin).The pair of projecting pieces 24 c ₂ at the both end portions play arole of embankments (or banks) to block objects, such as dirt, fromentering a space between the projecting pieces 24 c ₂.

The base portion 24 c ₁ has a pair of grooves 24 c ₁₁ provided along alongitudinal direction at a center of a width direction and respectivelyhousing the pair of conductive cables 24 a.

A transverse plane of an outer surface of the base portion 24 c ₁opposite to the grooves 24 c ₁₁ has an arc shape; and a transverse planeof an outer surface of the projecting piece 24 c ₂ also has an arcshape.

A transverse plane of an outer surface of the pair of hooking pieces 24b ₂ of the support plate 24 b has an arcuate portion 24 b ₂₁ that iscontinuous with each arc projecting piece 24 c ₂ of the cover plate 24c, and also has a flat surface portion 24 b ₂₂.

To the base portion 24 c ₁, a pair of hemispherical ribs 24 c ₃ arerespectively provided at both end portions 24 ce and an intermediateportion 24 _(cc) of the pair of grooves 24 c ₁₁, the pair ofhemispherical ribs sandwiching the lead wire 24 a ₁ therebetween that ishoused in each groove 24 c ₁₁ so as to prevent the lead wire to bedisplaced (or misaligned). The hemispherical ribs 24 c ₃ need not be apair; and the hemispheric ribs may be in one place or may be placedalternately at equal intervals.

On both sides of each groove 24 c ₁₁ of the base portion 24 c ₁, a pairof ridges 24 c ₄ is provided along a longitudinal direction.

The conductive unit 24 contains each of the conductive cables 24 a ineach groove 24 c ₁₁ of the cover plate 24 c; and the support plate 24 bcovers the groove 24 c ₁₁ side; and then an inner surface of the supportplate 24 b comes in contact with the pair of ridges 24 c ₄ of the coverplate 24 c and is ultrasonic-welded with these ridges. Instead of theultrasonic welding, an adhesive may be used.

In the assembled conductive unit 24, the support plate 24 b is longer inlength than the cover plate 24 c; and each conductive cable 24 a islonger in length than the support plate 24 b, with the result that apart of both ends of each conductive cable 24 a is exposed to theoutside while being supported by the support plate 24 b.

In the above descriptions, the conductive cables 24 a are referred to asthe pair of conductive cables, but are not limited to this. For example,only one conductive cable may be used. In this case, the one cable mayhave two conductive cables inside, allowing the two cables to be onecable. This allows the one cable to be laid through one of the twogrooves 24 c ₁₁ (see FIG. 20).

Assembly of Extension Tube

In the following, one example of how the extension tube 20 is assembledwill be described.

Firstly the conductive unit 24 is inserted into the tube body 21; andthen the pair of male terminals 24 a ₂ of the conductive unit 24 isincorporated (or inserted) into the first connecting pipe unit 22, andthe pair of female terminals 24 a ₃ of the conductive unit 24 isincorporated (or inserted) into the second connecting pipe unit 23.

The pair of male terminals 24 a ₂ is inserted into the connecting pipebody 22 a of the first connecting pipe unit 22, is drawn from thedrawing port 22 a ₂₁ to the outside, and is fixed to the rib structure22 a ₂₂. The pair of male terminals 24 a ₂ fixed to the rib structure 22a ₂₂ projects from the rib structure 22 a ₂₂ in a longitudinaldirection. At this time, one end of the pair of hooking pieces 24 b ₂ ofthe support plate 24 b of the conductive unit 24 is placed on the pairof receiving pieces 22 a ₁₁ of the connecting pipe body 22 a.

Portions facing inner surfaces of the tube body 21 and the first andsecond connecting pipe units 22 and 23—i.e., outer surfaces of the pairof hooking pieces 24 b ₂ of the support plate 24 b and an outer surfaceof the cover plate 24 c—in the conductive unit 24 are configured to havean arc shape so that the conductive unit 24 can lay along the innersurfaces of the tube body 21 and the first and second connecting pipeunits 22 and 23.

Secondly the fragment 22 b and the cover 22 c are attached to theconnecting pipe body 22 a; and the fixed portion 22 a ₁ of theconnecting pipe body 22 a is inserted into one end of the tube body 21and is fixed thereto with an adhesive. At this time, the positioningconvex portion 22 a ₁₂ of the first connecting pipe unit 22 engages withone of the notches 21 n of the tube body 21 so as to position thepositioning convex portion.

The pair of female terminals 24 a ₃ is inserted into the connecting pipebody 23 a of the second connecting pipe unit 23, is drawn from thedrawing port 23 a ₂₁ to the outside, and is fixed to the rib structure23 a ₂₂. The pair of male terminals 24 a ₂ fixed to the rib structure 22a ₂₂ respectively communicate with a pair of openings provided on therib structure 22 a ₂₂. At this time, the other ends of the pair ofhooking pieces 24 b ₂ of the support plate 24 b of the conductive unit24 are respectively placed on the pair of receiving pieces 22 a ₁₁ ofthe connecting pipe body 23 a (see FIG. 22). This allows the both endsof the conductive unit 24 to be supported by the first and secondconnecting pipe units 22 and 23, and thus this makes it possible for theconductive unit 24 to keep its position uplifted (or put up) withoutbeing supported inside the tube body 21. Since the conductive unit 24 issupported by only the both ends of the first and second connecting pipeunits 22 and 23 each in the tube body 21, the tube body 21 need not haveany additional component parts, leading to its assembly at low cost andimprovement in assembly operation. To avoid any gap (or interstice)between the conductive unit 24 and the inner surface of the tube body 21that could be formed by warpage (or a curve) of the conductive unit, thesupport plate 24 b has the shape like the letter “U” whose transverseplane is shallow; and a transverse plane of the cover plate 24 c has theshape like the letter “W”; and these component parts each are providedwith a rib in a longitudinal direction.

Lastly the fragment 23 b and the cover 23 e are attached to theconnecting pipe body 23 a; and the fixed portion 23 a ₁ of theconnecting pipe body 23 a is inserted into the other end of the tubebody 21 and fixed thereto with an adhesive. At this time, thepositioning convex portion 23 a ₁₂ of the second connecting pipe unit 23engages with the other one of the notches 21 n of the tube body 21 so asto position the positioning convex portion.

The assembly of the extension tube 20 is now completed.

Intake Port Body

FIG. 23 illustrates a bottom view of an intake port body of the electricvacuum cleaner in accordance with Embodiment 1; FIG. 24 illustrates aside view of the intake port body illustrated in FIG. 23. FIG. 25illustrates a cross-section view of the intake port body taken from lineI-I of FIG. 23; and FIG. 26 illustrates a cross-section view of theintake port body taken from line II-II of FIG. 23.

As illustrated in FIG. 23 to FIG. 26, the intake port body 40 includesthe following component parts: a bottom plate 41 a; a top plate 41 bopposed to the bottom plate 41 a; a front plate 41 c and a rear plate 41d that are respectively placed at the front and at the back in a movingdirection (in a direction of an X arrow indicated in FIG. 23); and aleft plate 41 e and a right plate 41 f that are respectively placed onthe left and on the right of the top plate 41 b in the moving direction.

As illustrated in FIG. 23, the intake port body 40 includes thefollowing component parts: an intake port 41 that is provided to thebottom plate 41 a and extends in a right-and-left direction (in adirection of an A1 arrow); a connecting pipe 42 connected to the rearside of the intake port 41 through a connecting shaft 42 x; a rotarybrush 43 rotatably attached around an axis extending in a right-and-leftdirection in the intake port 41; a suction channel 16 connecting theintake port 41 to the connecting pipe 42 (see FIG. 25); a motor forrotary brush 44 driving the rotary brush 43 (see FIG. 26); a brush cover80 covering a left end of the rotary brush 43 (as illustrated in FIG.23); and a lifting detecting device 47 and wheels 54, all of which beingattached to the bottom plate 41 a.

As illustrated in FIG. 26, a motor output gear 50 fixed to a motoroutput shaft 46 of the motor for rotary brush 44 is fastened to a gear58 b attached to the rotary brush 43 with a timing belt 48.

Once a start-up switch is turned on with use of the operating portion 11e (see FIG. 1), and floor cleaning starts, the rotary brush 43 driven bythe motor for rotary brush 44 sweeps and collects dust on the floor, andthe dust is carried from the intake port 41 to the dust cup unit 12 (seeFIG. 1) through the suction channel 16 and the connecting pipe.

The lifting detecting device 47 has the following component parts: aswinging lever having a wheel; a switch body swingably supporting theswing lever; and a torsion coil spring biasing the swinging lever towardthe bottom side; and the switch body is connected with a circuit boardfor rotary brush-driving motor contained in the bottom plate 41 a; andthe wheel of the swinging lever is downwardly exposed from the bottomplate 41 a to the outside.

When the intake port body 40 is lifted and spaced away from the floor,the lifting detecting device 47 is triggered and forces to stop theoperation of the motor for rotary brush 44.

This intake port body 40 has a pair of lead wires that is placed thereinand is electrically connected with the motor for rotary brush 44 and thelifting detecting device 47; and the pair of lead wires are electricallyconnected with the pair of pin-shaped male terminals 42 a, respectively,the male terminals being provided to the connecting pipe 42.

The connecting pipe 42 has at its end a locking concave portion 42 b.

The intake port body 40 configured as described above is detachablyconnected with the second connecting pipe unit 23 of the extension tube20. Thus the pair of male terminals 42 b of the intake port body 40 arerespectively inserted into the pair of female terminals 24 a ₃ of theextension tube 20, and are electrically connected therewith; and thelocking nail 23 c ₃ of the locking member 23 c of the extension tube 20detachably locks into the locking concave portion 42 b of the intakeport body 40 (see FIG. 1, FIG. 13, and FIG. 14).

Embodiment 2

The extension tube 20 provided with the first and second connecting pipeunits 22 and 23 at both ends of the tube body 21 has been described inthe first embodiment. However, the first and second connecting pipeunits 22 and 23 may be omitted. In such a case, the extension tube isconfigured such that the male terminal and the female terminal at bothends of the conductive unit 24 are fixed to both interior ends of thetube body.

Embodiment 3

The extension tube for an electric stick vacuum cleaner has beendescribed in the first embodiment. However, the extension tube accordingto the present invention is also applicable to an electric canistervacuum cleaner.

CONCLUSIONS

The extension tube for the electric vacuum cleaner according to thepresent invention comprises a tube body and a conductive unit providedso as to be laid in the tube body,

-   -   wherein the conductive unit includes conductive cables and a        hollow plate that contains the conductive cables.

The extension tube for the electric vacuum cleaner according to thepresent invention may have configurations described below, and theseconfigurations may be combined with one another as appropriate.

(1) The hollow plate may have a support plate and a cover plate, thesupport and cover plates covering the conductive cable so as to sandwichthe conductive cable therebetween.

With this configuration, the conductive unit can be assembled easily.

(2) The conductive cable and the support plate may be longer than thetube body, the conductive cable may be longer than the support plate,and the support plate may be longer than the cover plate.

With this configuration, the connecting portions to be connected to theintake port body which has the motor and the rotary brush incorporatedtherein and the vacuum cleaner body are easily provided to both ends ofthe tube body.

(3) The support plate may include a base portion having a concavetransverse plane and a pair of hooking pieces provided along upper endportions of both side surfaces of the base portion.

With this configuration, when a pair of receiving pieces is provided tothe interior of the tube body or interiors of the connecting portions atboth ends of the tube body, the pair of hooking pieces at both ends ofthe conductive unit can be hooked and held on the pair of receivingpieces.

(4) The support plate may have, on the base portion, a flat bottomportion for receiving the cover plate, and

-   -   the cover plate may have an outer surface having an arc        transverse plane.

With this configuration, the conductive unit can be disposed along theinner surface of the cylindrical tube body, whereby a wide space throughwhich air passes can be ensured in the tube body.

(5) The cover plate may have a groove provided along a longitudinaldirection at a center of a width direction for individually housing theconductive cables.

With this configuration, conductive cables can be individually protectedin respective grooves, and insulation between the conductive cables canbe improved.

(6) The cover plate may have hemispherical ribs at both end portions andan intermediate portion of the groove, the hemispherical ribssandwiching the conductive cables housed in the groove to preventdisplacement of the conductive cables.

With this configuration, unsteady movement of the conductive cables inthe respective grooves and scratches caused by the unsteady movement canbe prevented, whereby performance for protecting the conductive cablesin the respective grooves can be enhanced.

The disclosed Embodiments should be recognized as exemplifications inall respects and should not be recognized as limitative. The scope ofthe present invention is not described by the expositions above but isdescribed in claims; and the scope of the present invention is intendedto include the meanings (or the contents) equivalent to the scope of theclaims and also include all alterations (and modifications) within theclaims.

INDUSTRIAL APPLICABILITY

The present invention is applicable to an extension tube for an electricvacuum cleaners such as stick vacuum cleaners and canister vacuumcleaners.

REFERENCE SIGNS LIST

-   1 Electric vacuum cleaner-   20 Extension tube-   21 Tube body-   24 Conductive unit (conductive section)-   24 a Conductive cable-   24 b Support plate-   24 b ₁ Base part-   24 b ₂ Hook piece-   24 c Cover plate-   24 c ₁₁ Groove-   24 c ₃ Hemisphere rib-   24 x Hollow plate

1. An extension tube for an electric vacuum cleaner comprising: a tubebody; and a conductive unit provided so as to pass through the tubebody, wherein the conductive unit includes conductive cables and ahollow plate accommodating the conductive cables.
 2. The extension tubeaccording to claim 1, wherein the hollow plate has a support plate and acover plate, the support and cover plates covering the conductive cableso as to hold the conductive cable therebetween.
 3. The extension tubeaccording to claim 2, wherein the conductive cable and the support plateare longer than the tube body, the conductive cable is longer than thesupport plate, and the support plate is longer than the cover plate. 4.The extension tube according to claim 2, wherein the support plateincludes a base part having a recessed cross-section and a pair of hookpieces provided along upper ends of both lateral surfaces of the basepart.
 5. he extension tube according to claim 4, wherein the supportplate has, on the base part, a flat bottom part for receiving the coverplate, and the cover plate has an outer face having an arccross-section.
 6. The extension tube according to claim 2, wherein thecover plate has a groove provided along a longitudinal direction in awidthwise central part for individually housing the conductive cables.7. The extension tube according to claim 6, wherein the cover plate hashemisphere ribs at both ends and an intermediate part of the groove, thehemisphere ribs holding the conductive cables housed in the groove toprevent displacement of the conductive cables.